From 26de2b79c2918a1b6e0dbacc5cae323df0f37a0c Mon Sep 17 00:00:00 2001
From: Tom Hubrecht <github@mail.hubrecht.ovh>
Date: Sun, 23 Nov 2025 15:02:19 +0100
Subject: [PATCH] nix/develop: Set default outputs attribute

When using `builtins.derivation`, the `outputs` list can be omitted, and
in that case, it defaults to `[ "out" ]`, set this default when building
the shell derivation for `nix develop`

Fixes: #556
Change-Id: I4dc77d060f30ee499e186ec919de30bd3e5c53bb
---
 lix/nix/develop.cc | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lix/nix/develop.cc b/lix/nix/develop.cc
index 202d5fdbb..b9640d2e2 100644
--- a/lix/nix/develop.cc
+++ b/lix/nix/develop.cc
@@ -257,6 +257,10 @@ try {
         output.second = DerivationOutput::InputAddressed { .path = StorePath::dummy };
         drv.env[output.first] = "";
     }
+
+    // outputs default to [ "out" ]
+    drv.env.try_emplace("outputs", "out");
+
     auto hashesModulo = TRY_AWAIT(hashDerivationModulo(*evalStore, drv, true));
 
     for (auto & output : drv.outputs) {